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Arequipa-Antofalla
Arequipa-Antofalla is a basement unit underlying the central Andes in northwestern Argentina, western Bolivia, northern Chile and southern Peru. Geologically, it corresponds to a craton, terrane or block of continental crust. Arequipa-Antofalla collided and amalgamated with the Amazonian craton about 1000 million years ago during the Sunsás orogeny. As a terrane, Arequipa-Antofalla was ribbon-shaped during the Paleozoic The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma a ..., a time when it was bounded in the west by the Iapetus Ocean and in the east by the Puncoviscana Ocean. References Cratons Geology of Argentina Geology of Bolivia Geology of Chile Geology of Peru Terranes Precambrian South America Geology of the Andes {{SouthAm-geologic-formation-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Puncoviscana Formation
Puncoviscana Formation () is a formation (geology), formation of sedimentary rock, sedimentary and metamorphic rock, metasedimentary rocks Ediacaran, Late Ediacaran and Cambrian, Lower Cambrian age, estimated at between 700 and 535 Ma, that crop out in the Argentine Northwest. Most of the formation lies in Jujuy Province, Jujuy, Salta Province, Salta and Tucumán Province albeit some authors extend the formation further south to the Sierras Pampeanas near Córdoba, Argentina, Córdoba. There are various tectonic interpretations on the origin and type of sedimentary basin that accumulated Puncoviscana Formations sediments. An early interpretation was that the sediments originated from a passive marginal basin of the ancient continent Gondwana. Others suggested an craton, intra-cratonic rift or aulacogen basin between Río de la Plata craton, Río de la Plata-Pampia Craton and Arequipa-Antofalla, Arequipa Massif. Yet other hypotheses revolve around the idea that the Puncoviscana Form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iapetus Ocean
The Iapetus Ocean (; ) existed in the late Neoproterozoic and early Paleozoic eras of the geologic timescale (between 600 and 400 million years ago). It was in the southern hemisphere, between the paleocontinents of Laurentia, Baltica and Avalonia. The ocean disappeared with the Acadian, Caledonian and Taconic orogenies, when these three continents joined to form one big landmass called Euramerica. The "southern" Iapetus Ocean has been proposed to have closed with the Famatinian and Taconic orogenies, meaning a collision between western Gondwana and Laurentia. Because the Iapetus Ocean was positioned between continental masses that would at a much later time roughly form the opposite shores of the Atlantic Ocean, it can be seen as a sort of precursor of the Atlantic, and the process by which it opened shares many similarities with that of the Atlantic's initial opening in the Jurassic. The Iapetus Ocean was therefore named for the titan Iapetus, who in Greek mythology was the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terrane
In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its distinctive geologic history, which is different from the surrounding areas—hence the term "exotic" terrane. The suture zone between a terrane and the crust it attaches to is usually identifiable as a fault. A sedimentary deposit that buries the contact of the terrane with adjacent rock is called an overlap formation. An igneous intrusion that has intruded and obscured the contact of a terrane with adjacent rock is called a stitching pluton. There is also an older usage of the term ''terrane'', which described a series of related rock formations or an area with a preponderance of a particular rock or rock group. Overview A tectonostratigraphic terrane did not necessarily originate as an independent microplate, since it may not contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basement (geology)
In geology, basement and crystalline basement are crystalline rocks lying above the mantle and beneath all other rocks and sediments. They are sometimes exposed at the surface, but often they are buried under miles of rock and sediment. The basement rocks lie below a sedimentary platform or cover, or more generally any rock below sedimentary rocks or sedimentary basins that are metamorphic or igneous in origin. In the same way, the sediments or sedimentary rocks on top of the basement can be called a "cover" or "sedimentary cover". Basement rock consists of continental crustal rock which has been modified several times through tectonic events including deformation, metamorphism, deposition, partial melting and magmatism. Continental crust Basement rock is the thick foundation of ancient, and oldest, metamorphic and igneous rock that forms the crust of continents, often in the form of granite. Basement rock is contrasted to overlying sedimentary rocks which are laid down ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GSA Bulletin
The ''Geological Society of America Bulletin'' (until 1960 called ''The Bulletin of the Geological Society of America'' and also commonly referred to as ''GSA Bulletin'') is a peer-reviewed scientific journal that has been published by the Geological Society of America since 1890. Its first editor was William John McGee.Eckel, Edwin, 1982, GSA Memoir 155, The Geological Society of America — Life History of a Learned Society, p. 79., . According to the ''Journal Citation Reports'', the journal has a 2016 impact factor of 4.212. See also *List of scientific journals in earth and atmospheric sciences This list presents notable scientific journals in earth and atmospheric sciences and its various subfields. Multi-disciplinary Atmospheric science Geochemistry * ''Chemical Geology'' * '' Geochimica et Cosmochimica Acta'' * '' Geostan ... References External links * Geological Society of America English-language journals Geology journals Bimonthly journals { ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Peru
The geology of Peru includes ancient Proterozoic rocks, Paleozoic and Mesozoic volcanic and sedimentary rocks, and numerous basins and the Andes Mountains formed in the Cenozoic. Geological history, stratigraphy & tectonics The oldest rocks in Peru date to the Precambrian and are more than two billion years old. Along the southern coast, granulite and charnockite shows reworking by an ancient orogeny mountain building event. Situated close to the Peru-Chile Trench, these rocks have anomalously high strontium isotope ratios, which suggest recent calc-alkaline volcanism. In the Eastern Cordillera of Peru, Precambrian magmatism in the Huanuco region produced ultramafic, mafic and felsic rocks, including serpentinite, meta-diorite, meta-gabbro, meta-tonalite and diorite and granite that intruded after the first phase of orogenic tectonic activity. The basement of the Central Andean orogeny includes the rocks of the Arequipa Massif, which reach granulite grade on the sequence of me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Chile
The geology of Chile is a characterized by processes linked to subduction, such as volcanism, earthquakes, and orogeny. The building blocks of Chile's geology were assembled during the Paleozoic Era when Chile was the southwestern margin of the supercontinent Gondwana. In the Jurassic, Gondwana began to split, and the ongoing period of crustal deformation and mountain building known as the Andean orogeny began. In the Late Cenozoic, Chile definitely separated from Antarctica, and the Andes experienced a significant rise accompanied by a cooling climate and the onset of glaciations. The subduction interactions shaped four main morphostructures of Chile: the Andes, the Intermediate Depression, the Coast Range, and the Peru–Chile Trench off the coast. Since Chile is on an active continental margin, it has many volcanoes. Almost the entire country is subject to earthquakes arising from strains in the Nazca and Antarctic plates or shallow strike-slip faults. Northern Chile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Bolivia
The geology of Bolivia comprises a variety of different lithologies as well as tectonic and sedimentary environments. On a synoptic scale, geological units coincide with topographical units. The country is divided into a mountainous western area affected by the subduction processes in the Pacific and an eastern lowlands of stable platforms and shields. The Bolivian Andes is divided into three main ranges; these are from west to east: the Cordillera Occidental that makes up the border to Chile and host several active volcanoes and geothermal areas, Cordillera Central (in some contexts also called Cordillera Oriental) once extensively mined for silver and tin and the relatively low Cordillera Oriental that rather than being a range by its own is the eastern continuation of the Central Cordillera as a fold and thrust belt. Between the Occidental and Central Cordillera the approximately 3,750-meter-high Altiplano high plateau extends. This basin hosts several freshwater lakes, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Argentina
The geology of Argentina includes ancient Precambrian basement rock affected by the Grenville orogeny, sediment filled basins from the Mesozoic and Cenozoic as well as newly uplifted areas in the Andes. Geologic history, stratigraphy and tectonics The oldest rocks in Argentina date to the Precambrian. Strontium, oxygen and carbon isotope data from carbonate rocks in the Sierra de Pie de Palo are part of an ophiolite unit related to the Grenville orogeny, formed as cover rock in the Appalachian margin of the continent Laurentia around 720 million years ago. These Neoproterozoic age rocks are believed to have formed above much older Archean craton rock. Throughout the late Proterozoic, sections of Argentina were part of a metamorphic mobile belt adjacent to the Brazilian Shield. Regional metamorphism produced scheelite belts and wolframite in parts of San Luis and Cordoba Provinces. To the north, along the Bolivian border in the Altiplano, drilling has revealed Precambrian Hornblen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cratons
A craton ( , , or ; from "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates; the exceptions occur where geologically recent rifting events have separated cratons and created passive margins along their edges. Cratons are characteristically composed of ancient crystalline basement rock, which may be covered by younger sedimentary rock. They have a thick crust and deep lithospheric roots extending several hundred kilometres into Earth's mantle. Terminology The term ''craton'' is used to distinguish the stable portion of the continental crust from regions that are more geologically active and unstable. Cratons are composed of two layers: a continental ''shield'', in which the basement rock crops out at the surface, and a '' platform'' which overl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of South American Earth Sciences
The ''Journal of South American Earth Sciences'' is a peer-reviewed scientific journal published by Elsevier. It covers the earth sciences, primarily on issues that are relevant to South America, Central America, the Caribbean, Mexico, and Antarctica. The journal was established in 1988 and the editor-in-chief is James Kellogg (University of South Carolina). According to the ''Journal Citation Reports'', the journal has a 2012 impact factor of 1.533. See also *'' Ameghiniana'' *''Andean Geology ''Andean Geology'' (formerly ''Revista Geológica de Chile'') is a peer-reviewed scientific journal published three times per year by the National Geology and Mining Service, Chile's geology and mining agency. The journal covers the field of geo ...'' *'' Brazilian Journal of Geology'' *'' Latin American Journal of Sedimentology and Basin Analysis'' *'' Revista de la Asociación Geológica Argentina'' References External links * Geology journals Geology of South America Geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
